• Food Science of Animal Resources
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• v.23 no.4
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• pp.327-332
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• 2003

This study was conducted to investigate the characteristics of strains which were isolated from market milk treated with ESL(extended shelf life) and conventional system, and to compare the microbiological quality of ESL milk with conventional milk. In order to characterize the isolated strains, purification, Gram staining, spore staining, catalase, oxidase, motility test, and identification by means of automatic identificator were performed. The results obtained are as follows: total 364 selected strains were analyzed in this study. Depending upon the isolated source, the number of strains from conventional milk was found to be Higher than ESL-milk. By means of grouping of total strains, Bacillus ssp. and Staphylococcus ssp. showed to be predominant. But most of strains were distributed with various groups except Lactobacillus ssp. When the isolates were compared with milk process methods, Enterococcus ssp. was detected much on market milk treated with LTLT pasteurization. Also, Pseudomonas ssp. was detected much on conventional milk treated with UHT pasteurization. By comparison with genus groups depending upon storage temperature of market milk, the higher milk storage temperature increased, the most frequency detected Bacillus ssp. increased. Also, Pseudomonas ssp. was detected most frequently at 10$^{\circ}C$ storage condition. Generally this genus derived from post-contamination during milk processing and related to the quality of market milk during chilled system. In conclusion, it was shown that ESL system reduced post-contamination during milk process, following the improvement of product quality and life cycle during the distribution of market milk.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.7-14
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• 2003

Physico-chemical and sensory characteristics of six dongchimi cultivars were evaluated. Moisture and sugar contents were 94.2% and $4.30^{\circ}Brix$ for three spring radish cultivars, while 92.9% and $7.30^{\circ}Brix$ for three autumn ones. pH $(5.7{\sim}6.1)$ and acidity $(0.09{\sim}0.12%)$ did not show significant differences among cultivars. pH decreased steadily up to 21 days to reach optimum pH of 4.0. The maximum number of total lactic acid bacteria, $10^8{\sim}10^9\;CFU/mL$, was reached at pH 4.0. The final acidity of spring radishes was lower than that of autumn ones, and was proportional to the sugar content of the radishes. The firmness of spring radish decreased rapidly compared to the autumn ones. Cheongbok was found suitable for dongchimi, because its firmness level was maintained around $165.0{\times}10^3\;N/m^2$ at 35 days. Sensory evaluation revealed 96371 among spring radishes and cheongbok among autumn radishes scored high in firmness, chewiness, flavor, and overall acceptance. These results suggest that autumn radishes are suitable for dongchimi fermentation with cheongbok being the best among the cultivars.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.196-203
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• 2002

Effect of different levels (0 ,0.05, 0.15, 0.25%) of xanthan gum on kakdugi fermentation was investigated by analyzing physicochemical and sensory characteristics during fermentation at 2$0^{\circ}C$. During fermentation, pH was maintained higher, and total acidity and number of lactic acid bacteria, maintained lower in xanthan gum groups, especially in 0.05% addition group than control. Free sugar amount were higher in xanthan gun groups than control, and glucose and fructose which were the major free sugars, decreased rapidly during fermentation, whereas mannitol increased in all samples, especially in xanthan gum groups. Liquid content of kakdugi was smaller in 0.05% xanthan gum group than control. Viscosity of kakdugi liquid decreased rapidly whereas initial viscosity was maintained in xanthan gum groups. Hardness decreased during fermentation, but at the 7th day of fermentation was higher in 0.05% xanthan gum group than control. The result of sensory evaluation shows that there were no significant difference in sour odor, moldy, sour taste and savory taste among samples. Starch taste was higher in 0.15% or 0.25% xanthan gum, but there is no difference in 0.05% group, compared to control. Overall preference until the 5th day of fermentation, xanthan gum group was not significantly different from that of control but at the 7th day of fermentation, 0.05% addition group was significantly higher than control.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1158-1165
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• 1997

This study was designed to investigate the changes in microflora and enzyme activities of traditional kochujang during aging, which was prepared with a meju fermented for various periods of time. The number of bacteria was highest in all samples after 30 days of fermentation at $20^{\circ}C$, while that of mold in kochujang prepared with a 40-day- or 60-day-fermented meju was highest at 15th day of aging when yeast appeared. The activities of carbohydrases and proteases were highest in kochujang prepared with a 40-day-fermented meju followed by a 60-day-fermented meju. These results suggest that kochujang prepared with a meju aged for 40 days had the highest quality in terms of physicochemical, microbiological and enzyme activities of kochujang during fermentation.

• The Journal of the Convergence on Culture Technology
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• v.8 no.1
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• pp.591-596
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• 2022

Various COVID-19 quarantine guidelines and measures are being taken by country at the WHO, but the number of confirmed cases has not decreased significantly. In order to prevent the inflow and outflow of COVID-19 through individual droplets, it is mandatory to wear a mask anytime, anywhere. However, as virus bacteria entering the mask amplify, it pollutes the mask and causes a disgusting smell. In this paper, a new method of preventing the spread of COVID-19 was proposed by sterilizing the mask with a dental gait spray introduced into the mask that has been used for a long time. Dental gargle water is usually produced by electrolysis of tap water, and the unstable ion water (HOCl) dissolved in water penetrates the cell barrier of various viruses and fails to act in its nucleus, causing water to self-purify. As a result of the experiment, when the mask used for a long time was washed with gargle water spray, the washed mask was dried after 10 minutes, and the smell of virus droplets or saliva almost disappeared. In particular, as a result of MOS testing the fit of the subjects who participated in the mask cleaning, it was excellent at 4.4 on average. Therefore, the mask was disposable, but if the spray was washed in the proposed method more than twice a day, the mask could be used in a comfortable state for more than a week.

• Journal of Marine Life Science
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• v.5 no.2
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• pp.51-57
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• 2020

Disinfection and maintenance of rearing water in aquaculture is an essential element for the prevention of fish diseases. This is especially important in recirculating aquaculture systems (RAS) in which fish are reared at high density using recycled water. In this study, tilapia was reared in two different RAS (one with plasma generator - PW system, another without plasma generator - No PW system). In plasma treated group, UVT% of water was improved clearly, and the number of heterotrophic bacteria decreased significantly after 40 days. Total weight gain of tilapia in PW system was significantly higher, and other growth indicators were also relatively higher although not statistically significant. In addition, the fish in PW system had a 100% survival rate, and there were no histological differences between fish from both systems. Fish did not seem to be affected by the toxicity of ROS. In conclusion, it is expected that plasma water can effectively deactivate fish pathogens and improve the quality of rearing water.

• Analytical Science and Technology
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• v.35 no.6
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• pp.267-273
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• 2022

In this study, a quality evaluation was conducted to change the sell-by date of fish cakes to the use-by date. For product quality evaluation, storage conditions were set at 5, 10, and 15 ℃, and five tests of pH, acid value, volatile basic nitrogen, bacterial count, and coliform group were performed. As a result of the experiment, the quality safety limit period of fish cakes stored at 5 ℃ was 43 days, that of fish cakes stored at 10 ℃ were 30 days, and that of fish cakes stored at 15 ℃ was 7 days. Among the five test items used for quality evaluation, the quality-limit indicators were acid value, number of bacteria, and coliform groups. The index that determined the quality safety-limit period under the three storage conditions was the bacterial count. The sell-by date of the fish cake used in this experiment was 10 days. However, through quality evaluation, the use-by date at 10 ℃ was 28.5 days, which was calculated by multiplying the 30 days; the quality limit period, by a safety factor of 0.95. However, this study conducted a quality study on one item of fish cakes from a single company, and it was difficult to use the quality safety-limit period and use-by date set in this study universally. To change the sell-by date to the use-by date, extensive quality research on various products will be required. If this system is well established, it can help reduce food waste through proper consumption of food, and consumers will be able to consume food with confidence.

• Research in Plant Disease
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• v.17 no.3
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• pp.302-310
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• 2011

Elsinoe fawcettii is one of major pathogenic fungi which cause citrus scab diseases, resulting in fruit blemishes that reduce the economic value of fruit. By increasing interest to safe products of crops, the alternative methods of disease control is highly required. We investigated whether the 215 bacterial strains isolated from Jeju Island possess antifungal effect or suppression effect on the symptom development by Elsinoe fawcettii on citrus. Among them, three bacterial strains THJ 609-3, MRL408-3, and TRH423-3 that exhibited antifungal capacity against Elsinoe fawcettii were selected. To illustrate the disease suppression mechanism, pre-inoculation with the selected bacterial strains was carried out whether could suppress the citrus crab on the leaves. The observation with a fluorescence microscope revealed that the selected bacteria could decrease the number of fungal spores. The ratio of germ tube formation was also decreased by the selected bacterial strains at one day after fungus challenge. The strain THJ 609-3 was identified as Pseudomonas putida as a result of analyzing the internal transcript spaces of the rhizobacterial rDNA. The strains MRL 408-3 and TRH 423-3 were identified as Burkholderia gladioli. Our results may be valuable when the selected rhizobacterial strains used as the environment-friendly microbe for biological control on citrus scab caused by Elsinoe fawcettii.

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.293-302
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• 2016

To determine the dominant bacterial species during the Saeu-jeotgal ripening process, the cultivable bacterial population was examined over a 135-day period using six different growth media. The greatest numbers of bacteria were identified when marine agar was used for culture, with maximum cell density identified at day 65 (2.51 × 10⁷ colony forming units/g). Over the course of 135 days, the bacterial diversity was analyzed eight times. A total of 467 isolates, comprising 87 species from 42 genera, as well as 16 isolates belonging to previously unknown species, were identified. The number of species detected decreased from 39 at day 1 to 13 at day 135. The order of dominance at the genus level was as follows: Staphylococcus, Salimicrobium, Kocuria, and Psychrobacter. Staphylococcus and Salimicrobium accounted for 2% of the diversity at day 1, and then increased to 39% and 36%, respectively, at day 135. The dominant species Staphylococcus equorum, Salimicrobium salexigens, and Kocuria palustris accounted for 23.6%, 16.1%, and 10.9% of all isolates, respectively. Importantly, both St. equorum and Sm. salexigens remained viable at a NaCl concentration of 21% (w/v), which indicates their strong involvement in the ripening of Saeu-jeotgal.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1423-1430
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• 2014

This study investigated the effects of superheated steam (SHS) and high hydrostatic pressure (HHP) on the quality of Galbijjim. SHS cooking increased moisture and crude fat contents and decreased crude protein contents (P<0.05). The value of L was significantly higher upon SHS cooking compared to conventional cooking (CC), whereas a and b values were not significantly different among the samples. Hardness decreased more upon CC than SHS. The results of the safety storage experiment at refrigeration temperature showed that the total number of bacteria was lower in SHS-HHP than in CC-HHP. The thiobarbituric acid value increased to 0.70~1.56 mg malonaldehyde (MA)/kg in CC-HHP after 15 days, and SHS-HHP showed 0.69 (0 day)~1.24 (15 days, $10^{\circ}C$) mg MA/kg. Volatile basic nitrogen value was 18.07~36.76 mg% in CC-HHP, and that in SHS-HHP also increased to 17.06 (0 day)~35.76 mg% (15 days, $10^{\circ}C$). Overall, SHS cooking and HHP reduced microorganisms, which could improve product quality and sanitation.